Cross Lingual Transfer in Tulu Legal Comprehension: Script-Dependent Improvement and RAG-Induced Knowledge Conflict
Abstract
Low-resource languages without an adequate training corpus often use a related, higher-resource language as a scaffold for comprehension. Still, there is a need to develop rigorous evaluation methods to identify when models fail in cross lingual low-resource environments. Using the legal domain as a backdrop, three models (Llama3, Hex-1, Sarvam) were tested on the ability to classify legal complaints written in a low resource Dravidian language (Tulu). Transliterating queries across Dravidian scripts allowed models to gain a preliminary understanding of speakers' complaints without the use of wide scale training, though the level of comprehension was heavily script dependent (with Kannada - another relatively low-resource language - producing the strongest positive trend). Retrieving from a corpus of Kannada legal papers across a RAG framework caused mixed results. Some models had a weak positive trend in comprehension under certain conditions, but when models failed, it was often across two axes: fact substitution (fixating on specific passage excerpts that skewed reasoning) and confabulation (hallucination that had no basis in either query or corpus). Within low resource domains, results identify the model's parsing of information and subsequent reasoning as the source of reasoning failure, rather than corpus contents. Script-dependent comprehension and RAG robustness also seem to travel together. This is further supported by the reasoning-trace analysis and a statistical-honesty framework deployed - techniques that are more broadly applicable to low-resource multilingual RAG evaluation.
Figures & tables
| Condition | Script | Priming | RAG |
|---|---|---|---|
| A | English gloss | – | ✓ |
| B | Romanized Tulu | – | ✓ |
| C | Romanized Tulu | ✓ | ✓ |
| D | Kannada script | ✓ | ✓ |
| E | Kannada script | ✓ | – |
| F | Kannada script | – | ✓ |
| Query (gloss) | Reasoning trace |
|---|---|
| “I don’t know which court I should go to” | “The situation explicitly mentions ‘court’, indicating a problem related to the legal system.” |
| “Someone is living on my land without asking and won’t leave” | “…classic housing/trespass issue.” |
Appendix figures & tables13 assets
Supplementary material from the paper’s appendix.
Appendix
| ID | Primary | Secondary | English Gloss | Romanized Tulu |
|---|---|---|---|---|
| 1 | Housing | Consumer/Money/Debt | My landlord did not give back my money | enna dhani kasn vapas kortijer. |
| 2 | Work/Employment | – | My employer did not pay me this month | enna dhani i tingolda sanbalan kortijer. |
| 3 | Torts/Individuals | – | Someone broke my fence and did not fix it | era enna belin hal maltd nanla sari maltijer. |
| 4 | Consumer/Money/Debt | – | I gave someone money and they disappeared | yan erega kas kori bokka akulu tappayer. |
| 5 | Land/Property | – | My neighbor took my land | enna baritakulu enna jagan detter. |
| ID | \kannadafont Kannada |
|---|---|
| 1 | \kannadafont ಎನ್ನ ಧನಿ ಕಾಸ್ನ್ ವಾಪಸ್ ಕೊರ್ತಿಜೇರ್. |
| 2 | \kannadafont ಎನ್ನ ಧನಿ ಈ ತಿಂಗೋಲ್ದ ಸಂಬಳನ್ ಕೊರ್ತಿಜೇರ್. |
| 3 | \kannadafont ಏರಾ ಎನ್ನ ಬೇಲಿನ್ ಹಾಳ್ ಮಲ್ತ್ದ್ ನನ್ಲಾ ಸರಿ ಮಲ್ತಿಜೇರ್. |
| 4 | \kannadafont ಯಾನ್ ಏರೇಗಾ ಕಾಸ್ ಕೊರಿ ಬೊಕ್ಕ ಅಕುಲು ತಪ್ಪಾಯೇರ್. |
| 5 | \kannadafont ಎನ್ನ ಬರೀತಕುಲು ಎನ್ನ ಜಾಗನ್ ದೆತ್ತೇರ್. |
| \kannadafont | ||
|---|---|---|
| \kannadafont Kannada | Romanized | Meaning |
| \kannadafont ಆಂಜೊ | aanjo | man |
| \kannadafont ಆಲ್ | al | she |
| \kannadafont ಬಾಲೆ | baale | child |
| \kannadafont ಮೀನ್ | meen | fish |
| \kannadafont ಪೋಪಿನಿ | popini | to go |
| \kannadafont | ||
|---|---|---|
| \kannadafont Kannada | Romanized | Meaning |
| \kannadafont ಯಜಮಾನ | yejamaana | landlord/owner |
| \kannadafont ಧನಿ | dhani | landlord/employer (authority figure over you) |
| \kannadafont ಕಾಸು | kas | money |
| \kannadafont ಜಾಗ | jagga | land |
| \kannadafont ಇಲ್ಲ್ | ille | house |
| Llama3 | Hex-1 | Sarvam | |||||
|---|---|---|---|---|---|---|---|
| Script | Tier | Hits@1 | Hits@3 | Hits@1 | Hits@3 | Hits@1 | Hits@3 |
| Romanized | bare | 16.7% | 46.7% | 16.7% | 65.0% | 33.3% | 61.7% |
| sparse | 13.3% | 43.3% | 18.3% | 55.0% | 30.0% | 60.0% | |
| full | 31.7% | 56.7% | 25.0% | 61.7% | 40.0% | 71.7% | |
| Kannada | bare | 46.7% | 76.7% | 41.7% | 68.3% | 48.3% | 76.7% |
| sparse | 51.7% | 75.0% | 45.0% | 76.7% | 46.7% | 78.3% | |
| Condition | Llama3 H1 | Llama3 H3 | Hex-1 H1 | Hex-1 H3 | Sarvam H1 | Sarvam H3 | n |
|---|---|---|---|---|---|---|---|
| A | 61.7% | 95.0% | 86.7% | 98.3% | 91.7% | 100.0% | 60 |
| B | 16.7% | 56.7% | 16.7% | 50.0% | 28.3% | 63.3% | 60 |
| C_sparse | 16.7% | 46.7% | 11.7% | 46.7% | 31.7% | 61.7% | 60 |
| C_full | 18.3% | 53.3% | 25.0% | 63.3% | 45.0% | 73.3% | 60 |
| D_sparse | 26.7% | 66.7% | 41.7% | 68.3% | 55.0% | 75.0% | 60 |
| D_full | 23.3% | 68.3% | 46.7% | 80.0% | 60.0% | 80.0% | 60 |
| Comparison (Hits@1) | Llama3 | Hex-1 | Sarvam |
|---|---|---|---|
| Baseline comprehension (binomial test vs. chance/majority) | |||
| H (Kannada bare) vs. chance (12.5%) / majority (25%) | / | / | / |
| D_full vs. majority-class (25%) | (ns) | *** | *** |
| Priming effects (Fisher’s exact) | |||
| E_full vs. H (Kannada full-priming effect) | (ns) | (ns) | (ns) |
| L_full vs. J (Malayalam full-priming effect) | * | * | ** |
| Model | Bare | Sparse prime | Full prime | RAG only | RAG+sparse | RAG+full |
|---|---|---|---|---|---|---|
| Llama3 | 46.7¿16.7*** | 51.7¿13.3*** | 60.0¿31.7** | 25.0¿16.7 (ns) | 26.7¿16.7 (ns) | 23.3¿18.3 (ns) |
| Hex-1 | 41.7¿16.7** | 45.0¿18.3** | 60.0¿25.0*** | 38.3¿16.7* | 41.7¿11.7*** | 46.7¿25.0* |
| Sarvam | 48.3¿33.3 (ns) | 46.7¿30.0 (ns) | 66.7¿40.0** | 53.3¿28.3** | 55.0¿31.7* | 60.0¿45.0 (ns) |
| Model | Tier | E-right/D-wrong | D-right/E-wrong | Ratio |
|---|---|---|---|---|
| Llama3 | full | 26 | 4 | 6.5:1 |
| Llama3 | sparse | 20 | 5 | 4.0:1 |
| Hex-1 | full | 10 | 2 | 5.0:1 |
| Hex-1 | sparse | 8 | 6 | 1.3:1 |
| Sarvam | full | 7 | 3 | 2.3:1 |
| Sarvam | sparse | 4 | 9 | 0.4:1 |
| Judge language | Hits@1 | Hits@3 | Passages retained | No-RAG fallback |
|---|---|---|---|---|
| Kannada script | 25.0% (5/20) | 65.0% (13/20) | 2.85 / 3 | 0/20 |
| English gloss | 60.0% (12/20) | 80.0% (16/20) | 1.65 / 3 | 3/20 |
| Case | Case No. | Court | CNR / Date |
|---|---|---|---|
| Sridhar P. v. Ramesh | C.C. No. 5343/2024 | 4th Addl. Small Causes Court & ACJM, Bengaluru Urban | KABC020187742024, 3 Jun 2025 |
| Amith Ramachandra v. Shantha | P.C.R. No. 3981/2025 | 41st Addl. Chief Judicial Magistrate, Bengaluru Urban | KABC030166202025, 6 May 2025 |
| Sadashiva Shetty v. Vijaya Bank | R.A. No. 43-2001 | Principal Civil Judge (Sr. Div.) & CJM, Udupi | KAUP020002942001, 24 Jan 2009 |
| State v. Sudhakar Pai | C.C. No. 1357/2016 | JMFC 2nd Court, Mangaluru | KADK070014602016, 18 Oct 2016 |
| Nikitha A. v. Santhosh Ghatke | Crl.Misc. No. 127/2023 | JMFC Traffic Court VI, Bengaluru Urban | KABC080042862023, 4 Jul 2025 |
| Akkamma v. Ramesh Patil | Cri.Misc. No. 17/2018 | Principal Civil Judge & JMFC, Byadgi, Haveri | KAHV210000762018, 1 Aug 2018 |