diff --git a/server/logger.js b/server/logger.js
index cf112369..30dcd1e7 100644
--- a/server/logger.js
+++ b/server/logger.js
@@ -12,6 +12,6 @@ const transports = process.env.NODE_ENV === 'test'
   ]
 
 module.exports = new (winston.Logger)({
-  level: process.env.LOG_LEVEL || process.env.NODE_ENV === 'development' ? 'debug' : 'info',
+  level: process.env.LOG_LEVEL || (process.env.NODE_ENV === 'development' ? 'debug' : 'info'),
   transports
 })
diff --git a/test/unit/logger.test.js b/test/unit/logger.test.js
new file mode 100644
index 00000000..9e9c00cf
--- /dev/null
+++ b/test/unit/logger.test.js
@@ -0,0 +1,34 @@
+'use strict'
+
+const {assert} = require('chai')
+
+describe('Logger', () => {
+  beforeEach(() => {
+    jest.resetModules()
+  })
+
+  afterEach(() => {
+    delete process.env.LOG_LEVEL
+    process.env.NODE_ENV = 'test'
+  })
+
+  it('initialises log level when specified in LOG_LEVEL', () => {
+    process.env.LOG_LEVEL = 'silly'
+    const logger = require('../../server/logger')
+    assert.equal(logger.level, 'silly')
+  })
+
+  it('initialises log level to debug in development', () => {
+    delete process.env.LOG_LEVEL
+    process.env.NODE_ENV = 'development'
+    const logger = require('../../server/logger')
+    assert.equal(logger.level, 'debug')
+  })
+
+  it('initialises log level to info in production', () => {
+    delete process.env.LOG_LEVEL
+    process.env.NODE_ENV = 'production'
+    const logger = require('../../server/logger')
+    assert.equal(logger.level, 'info')
+  })
+})