Running jest tests without sequential flag (-i) fails due to "deadlock detected"

Lots of tests fail without using "-i" , e.g "$yarnpkg jest -i models"

Example of error message is :

FAIL models src/models/tests/team.test.js (11.965 s) ● Team Model › non-global teams must have an associated object

error: TRUNCATE TABLE chat_threads CASCADE - deadlock detected

  14 | 
  15 |         if (tablename !== 'migrations') {
> 16 |           return db.raw(`TRUNCATE TABLE ${tablename} CASCADE`)
     |                     ^
  17 |         }
  18 | 
  19 |         return true

  at Object.raw (node_modules/knex/lib/util/make-knex.js:114:30)
  at Function.raw (node_modules/knex/lib/util/make-knex.js:90:29)
  at map (src/models/__tests__/_clearDb.js:16:21)
      at Array.map (<anonymous>)
  at dbCleaner (src/models/__tests__/_clearDb.js:12:12)

Error seems to be in the _clearDb.js file, related to it's custom TRUNCATE sql command.