diff --git a/test/consensus-test.js b/test/consensus-test.js
index 03503d442..678733942 100644
--- a/test/consensus-test.js
+++ b/test/consensus-test.js
@@ -36,6 +36,39 @@ describe('Consensus', function() {
     assert(consensus.verifyPOW(hash, bits));
   });
 
+  it('should not verify proof-of-work if bits is negative', () => {
+    const bits = 0x1d00ffff * -1;
+
+    const hash = Buffer.from(
+      '672b3f1bb11a994267ea4171069ba0aa4448a840f38e8f340000000000000000',
+      'hex'
+    );
+
+    assert(!consensus.verifyPOW(hash, bits));
+  });
+
+  it('should not verify proof-of-work if bits is zero', () => {
+    const bits = 0;
+
+    const hash = Buffer.from(
+      '672b3f1bb11a994267ea4171069ba0aa4448a840f38e8f340000000000000000',
+      'hex'
+    );
+
+    assert(!consensus.verifyPOW(hash, bits));
+  });
+
+  it('should not verify proof-of-work if bits is too high', () => {
+    const bits = 0x1d00ffff * 2;
+
+    const hash = Buffer.from(
+      '672b3f1bb11a994267ea4171069ba0aa4448a840f38e8f340000000000000000',
+      'hex'
+    );
+
+    assert(!consensus.verifyPOW(hash, bits));
+  });
+
   it('should convert bits to target', () => {
     const bits = 0x1900896c;
     const target = consensus.fromCompact(bits);
@@ -64,4 +97,51 @@ describe('Consensus', function() {
     assert(consensus.hasBit(0x20000003, 1));
     assert(consensus.hasBit(0x20000003, 0));
   });
+
+  it('should return BN(0) from fromCompact when called with a zero', () => {
+    const target = consensus.fromCompact(0);
+    const bnZero = new BN(0);
+
+    // assert that the return object is correct by type and value
+    assert.strictEqual(target.constructor.name, bnZero.constructor.name);
+    assert.strictEqual(target.toString(), bnZero.toString());
+  });
+
+  it('should return BN(0) from fromCompact when the passed in value right shifted 24 is less than three', () => {
+    const target = consensus.fromCompact(0x01000000);
+    const expected = new BN(0x00000000);
+
+    assert.strictEqual(target.toString(), expected.toString());
+  });
+
+  it('should return the correct value from fromCompact when called with 0x0fffffff', () => {
+    const target = consensus.fromCompact(0x0fffffff);
+    const expected = new BN(-664613918664295422187565936596221952n);
+
+    assert.strictEqual(target.toString(), expected.toString());
+  });
+
+  it('should return 0 from toCompact when called with BN(0)', () => {
+    const target = new BN(0);
+    const bits = consensus.toCompact(target);
+    const expected = 0;
+
+    assert.strictEqual(bits, expected);
+  });
+
+  it('should return 16842752 when the byteLength of the passed in value is less than three', () => {
+    const target = new BN(0x00000001);
+    const bits = consensus.toCompact(target);
+    const expected = 16842752;
+
+    assert.strictEqual(bits, expected);
+  });
+
+  it('should return correct value from toCompact when the param is negative and its byteLength is less than three', () => {
+    const target = new BN(-10000n);
+    const bits = consensus.toCompact(target);
+    const expected = 4294957296;
+
+    assert.strictEqual(bits, expected);
+  });
 });