← Back to HomeMulti-Criteria Decision Analysis

The Harm Matrix

Side-by-side comparison across 7 critical harm categories. Scores represent relative harm severity (0-100). The data is drawn from the updated MCDA framework published in the Journal of Psychopharmacology (2026), funded by the Canadian Institutes for Health Research.

Overdose Potential

stat_minus_1
Alcohol95/100

High — Directly lethal via respiratory depression. BAC >0.40% routinely fatal.

Cannabis0/100

Zero — No CB1 receptors in brainstem. Fatal overdose biologically impossible.

Organ & Body Damage

stat_minus_1
Alcohol90/100

Severe — WHO Group 1 carcinogen. Causes liver cirrhosis, cardiomyopathy, pancreatitis, and 7 types of cancer.

Cannabis20/100

Low-Moderate — Only combustion smoking irritates lungs. Vaping/edibles bypass this entirely.

Dependence Risk

stat_minus_1
Alcohol70/100

High (~15%). Withdrawal (delirium tremens) has 5% mortality — fatal seizures and cardiac arrest.

Cannabis35/100

Moderate (~9%). Withdrawal causes insomnia, irritability — physically safe.

Mental Health Impact

stat_minus_1
Alcohol80/100

Severe — Strongly correlated with depression, anxiety, suicide. Causes permanent cognitive decline.

Cannabis30/100

Conditional — Can trigger psychosis only in genetically predisposed individuals. Reversible cognitive effects.

Societal & Violent Impact

stat_minus_1
Alcohol90/100

Catastrophic — Only drug with direct pharmacological link to violence. 40%+ of violent crime, majority of domestic abuse.

Cannabis5/100

Minimal — Sedative and muscle relaxant. Inverse correlation with violence. Domestic violence drops after legalization.

Healthcare Burden (UK)

stat_minus_1
Alcohol85/100

£4.9B+ annually to NHS. Leading cause of premature mortality for ages 15-49.

Cannabis5/100

Minimal — Most costs are from policing prohibition, not health treatment.

Economic Cost (UK)

stat_minus_1
Alcohol88/100

£27B+ annually (healthcare, policing, crime, lost productivity).

Cannabis10/100

~£0 direct. The financial cost is artificially created by prohibition enforcement.

The Verdict Is Unambiguous

Alcohol is unambiguously and significantly more harmful than cannabis across almost every metric measured. If alcohol were discovered today, it would be classified as a highly restricted controlled substance.

Sources: Nutt et al. (2010, The Lancet); Updated Journal of Psychopharmacology (2026, CIHR-funded); Canadian Institutes for Health Research